Screw



June 9, 1942. w. A. PURTELL 2,285,460

SCREW Filed y 26, 1-959 /NVEN 7 WM/mm/lPur Z .ifiilllllllllii a Patented June 9,1942

UNITED STATES PATENT OFFICE SCREW William, A. Purtell, West Hartford, em, as-

signor to The Holo-Kromc Screw Corporation, a corporation of Connecticut Application May 26,1939, Serial No. 275,902

' 15 Claims. (ores-45) My invention relates to screws.

More particularly, it relates to screws of a type adapted to be produced by a modified form of the method and apparatus described and claimed in my copending application Serial No. 275,904, filed May 26, 1939; a further type of such screw also being described and claimed in mycopending applicationSerial No. 275,903, filed May 26,

It has among its objects to provide an improved socketed screw suitable for use in wood,

metal, or other materials. A further object of my invention is to provide such a screw having improved socket means of an improved conformation and adapted to cooperate in an improved at the other end with a head 4; this head 4 herein being provided with an improved socket,

' generally indicated at 5, in the top thereof, which is adapted to cooperate in an improved manner with a screw driver 'I, all as hereinafter more fully described.

Referring to the socket 5, it will be noted that while not limited to the number of flutes illustrated, I have shown herein six grooved or fluted portions 8 opening radially into the socket 5, such a number being found to be desirable in increasing the facility with which the socket may be formed, and also ,that with which a screw driver manner with a screw driver and to provide an improved target "for the latter. Still another object includes the provision of a such an improved screw wherein the socket forming aperture is of such improved structure as to facilitate the insertion of the screw driver and retain the screw thereon in such manner as markedly to speed up the process of screw insertion, while also increas ing the strength of the head and minimizin These and other view of my improved similar to that in Figure 2, the view being taken on line 34 of Figure 1;- v Fig. 4 is a section on line 4 4 of Figure 2;

Fig. 5 is a section on'line 5-5 of Figure 2;

Fig. 6 is a view similar to Figure 2 but showing a screw driver in process of insertion in the socket in the head'of the screw; I

Fig. 7 is a view similar to Figure 2, but with the screw driver inserted in the'socket;

Fig. 8 is a view similiar to Figure 3, but with the screw driver inserted in the socket; I

Fig. 9 is a side elevation of the driver, and p Fig. 10 is a view similiar to Figure 7 showing a modified form of screw driver in position'in the socket. e

In this illustrative construction, the screw, generally indicated at I, has a shank 2 provided at one end with suitable threads 3 thereon and 55 tions,

may be inserted in this socket. Further, it will be observed that each of these portions 8 is'provided with a-convexly curved, radially located, ribbon-like, end or outerwall 9 extending downward from the top of the head 4 to the bottom of the socket 5, as shown in Figure 2. As clearly appears from Figures 4 and 5, these walls 9 decrease slightly in width from the top to the bottom of the socket. Moreover, each of the portions 8 is provided with laterally'concave side walls in diverging from the opposite edges of the walls 9. Side walls I ll of adjacent fluted portions also intersect at the inner edges of these-walls l0, thereby forming avertically curved-edge II,

more steep in its inclination than the walls 9 and constituting the. apex of an' intermediate ab utment l2 provided between adjacent fluted portions 8.

Thus, the socket 5 .is provided with a large target or mouth, the whole area within a circle passing through the upper ends of the edges Hr beingopen. Further, the convex surfaces 9 are so disposed in this large mouth as to produce tool guiding surfaces leading gradually toward the axis and bottom of the socket, in such man-T ner that a screw driver extremity engaging at any point on these surfaces9 tends to be automatically centered. Attention is also directed to the fact that the angle of the inner ends of the convex surfaces 9, herein indicated at 9a, relative to the axis of the socket is so small as to enable a very definite binding or w'edging effect to be obtained at the inner end 9a of each surface 9,

this effect obviously decreasing as the socket flares'foutward toward the mouth of the socket where, in order to facilitate insertion of the screw driver, binding is not desired.

Receivable in my improved socket 5 is a screw driver I, which is adapted to cooperate therewith to enable improved results to be obtained. Here-' in, the driver I 'is provided with radial wing porgenerally indicated at l3, and correspondthe cohnection' of the screw and driver. ther, it will be apparent that when the screw ing in conformation to the" fluted portions 8 in which they are adapted to bereceived and fit, as shown in Figures '7 and 8. More particularly,

each of these portions 13 tapers toward the extremity of the driver and'has a concave, outer, ribbon-like, edge portion l4, corresponding to the wall 9 and adapted to engage the latteras shown in Figure 7, while each portion l3 also is provided with laterally convex side walls I5, corresponding to and engageable with the walls I and adapted to engage these walls I ll when the edge portions H are engaging the walls 9. Further, these walls I5 intersect on a concave line l6 as 7 shown in Figure 8, in such manner as,thereby to receive'the convex intersection ll -of the adjacent walls l0.

Asra result of the cooperation of my improved socket& and the driver I, when the latter has its working end inserted in the socket, the inner more abruptly angled portions 9a of theconvex surfaces 9 will engage corresponding portions on the inner ends of the surfaces l4 on'the wing portions l3 in such manner as to produce suflicient binding at the inner end of the socketlto insure as shown in these figures, the length of the working end of the screw driver is such as to space its inner endslightly from the bottom of the socket.

In the use of my improved construction, the

enlarged mouth provided in the socket 5 by the several large upper ends of the fluted portions 8, 40

is such as markedly to facilitate the insertion of the screw driver 1, the size of the opening or socalled "target thus provided for the screw driver. in the headof the screw, being such'as markedly to facilitate and speed up the insertion of the screws. Further, the convex surfaces 9 act to guide the smaller or entering ends of the .wing

Portions l3 of the screw driver I toward the axis of the screw, in such manner as thereby further to facilltate con action and disconnection of the driver and scr w. It will also be particularly noted that 'asthe screw driver moves inward with its concave surfaces ll riding along the convex surfaces 9, the-binding effect gradually increases until the inner ends of the walls II on the wing portions I 3 are quite snugly engaged with the inner portions v9* of the corresponding convex walls 9, the grip obtainable being such as to permit the driver to be handled substantially at will without the engagement of the walls [5 with the corresponding surfaces In on the latter thus acting to -minimize any tendency to mutilate the abutments H or tear the walls of the screw.

In Figure 10, I have illustrated a modified driver construction which. may be used, if desired. In this construction, instead of a surface II on the wing portion l3 of the screw driver, a

surface I1 is provided, which, while corresponding to the surface I I in having a cooperating binding or wedging pbrtlon at its inner end, slopes further away from the-corresponding sur- Fillrected to the more even distribution of the metgether of the screw and face 9 on the screw toward the mouth of the socket.- In this construction, obviouslythe inner end portions 9a of the various surfaces 9 will cooperate with the inner endslof the various surfaces I! to produce the desired binding effect;

even if the remainder of the surfaces l'l does not fit the remainder of the surface 9, all while continuing to obtain other advantages of my improved construction, heretofore described. a

As a result of my improved construction, it is made possible for the screws to be inserted in the workwith increased speed and facility, due to the larger target provided by my improved socket i and to the guiding action exertedby the convex surfaces on the screw driver. Further, the screw is securely maintained upon the driver by the wedging action in the shallow zone adjacent the bottom of'the socket, upog river and without any conscious connecting effort on the part of the user, while the binding or wedging actionis such a as, of course, to permit the ready withdrawal of the screw driver, or removal of the screw, whenever desired. Attention is also particularly dial in. the socket walls present in my improved construction which is such as to eliminate the need for severe displacements of the metal during the socket forming operation, and'also to produce a stronger head. Further, the construction is such as to enable the screws to be made quickly and satisfactorily in an ordinaryheader and eliminate necessity for shearing the top and the under surface of the head, all in such manner as markedly to reduce the manufacturing cost of the same.v These and other advantages of my improvements will, however, be clearly apparent to those skilled in the art.

'No claim is made herein to t e turning tool or driver, or' the combinationereof with the socketed screw, this subject matter being claimed in a divisional application Serial No. 433,031, flied March 2, 1942.

While I have in this application specifically described certain forms which my invention may assumein' practice, it will be understood that loss ofthescrew therefrom. Further, it will be bottom of the socket. Attention is also particu- I larly directed. to the fact that uponjturning of the driver about its axis, theiseveral side walls ,I 5 on the wing portions 13 thereof .will produce an effective turningmovement of the screw with aminimum of destructivecammingaction on the walls of the socket, tending ,to explode the latter;

these forms of the same are shown for purposes of illustration, and that the same may be modifled and my invention embodied in various other forms without departing, from its. spirit or the I scope of the appended claims.

What I claim as new Letters Patent is:

. 1. A socketed connector having a turnin socket therein, and turning toolbinding means including a binding portion adiacent'the bottomof said socket and disposed at increasingly acute binding angles toward said bottom, for enga ing a generally correspondingly angled reciprocably inserted tool at a binding angleadiacent the bottom ofsaidsocket.

2. A socketed connector having a turning socket therein, andfturging .tool-bi'n'tfing means the mere bringing toand desire secure by toward the bottom thereof and also having in creasingly acute binding angles on said portion.

4. A socketed connector having a turning socket therein including radially located'fluted portions, and turning tool binding means having binding portions on the bottom ends of certain of said fluted portions and disposed at increasingly acute binding angles toward the bottom of said socket.

5. A socketed screw having a turning socket therein including radially located fluted portions,

- and having elongated convex turning tool binding means around the inner end of said socket and disposed at increasingly acute binding angles toward the bottom of said socket.

6. A socketed screw having a turning socket therein including radially located fluted portions, and also having elongated convex turning tool binding end wall portions in certain of said fluted portions disposed at increasingly acute angles to the screw axis toward the bottom of said socket.

7. A socketed screw having a turning socket therein including radially located fluted portions, and also having convex end wall portions in said fluted portions, and side walls on said fluted portions having elongated binding portions adjacent the bottom of the socket disposed at increasingly sharp angles to the screw axis toward the bottom oi. said socket.

8. A socketed screw having a turning socket therein including radially located fluted portions and turningtool abutments therebetween, and also having convex end wall portions in said fluted portions, and binding portions on the edges of said abutments adjacent the socket axis having elongated binding portions adjacent the bottom of the socket-disposed at increasingly sharp angles to the screw axis toward the bottom of said socket. 9. A socketed screw having a turning socket therein including radially located fluted portions and turning. tool abutments therebetween, and alsohaving a plurality of binding walls in said socket leading toward the bottom thereof, the inner portions of said walls being convex and approaching the. axis of the screw at increasingly sharp binding angles.

l0. A socketed screw having a turning'socket therein including radially located flutedportions,

and also having end walls in said fluted portio the inner portions bisaid walls being convex and approachingthe axis of the screw at increasing- 1y sharp binding angles, and the remainder of said socket having like sharply angled binding surfaces therein disposed in a shallow transverse peripheral zone adjacent the bottom of the socket.

11. A socketed screw having aturning socket therein including radially located fluted portions, and having binding portions wholly in the inner end of said socket and comprising vertically convex binding surfaces on the inner ends of said binding portions and approaching the axis of the screw at increasingly sharp binding angles toward the bottom of the socket. I

' 12. A socketed screw having a turning socket therein including radially located fluted portions opening into said socket, and turning abutments between said fluted portions, said fluted portions having convex end walls and said walls having binding portions on their inner ends approaching the axis of the screw at increasingly sharp binding angles toward the-bottom of the socket and said abutment portions having longitudinally disposed convex binding portions between' their opposite sides.

13. A socketed screw having a turning socket therein including radially located fluted portions opening into 'said socket, and turning abutments between said fluted portions, said fluted portions having convex end walls and said walls having binding portions on their inner ends approaching the axis of the screw at increasingly sharp binding angles toward the bottom of the socket and also having side walls forming theside walls of said abutments and cooperating to form binding portions and intersecting along longitudinally disposed convex lines.

14. A socketed connector having a turning socket therein including radially located fluted portions disposed in intersecting longitudinal planes, around the axis of said socket and having short side walls on said portions cooperating to provide an enlarged axial target, and turning tool binding means disposed in the bottom of said socket having radially located binding portions disposed at increasingly sharp binding angles'toward the bottom of said socket.

15. A socketed connector having a turning socket therein including oppositely extended fluted portions disposed in the same longitudinal plane and a plurality of like oppositely located and equally spaced fluted portions disposed on opposite sides of said plane, said fluted -portions being disposed around the axis of said socket and adjacent fluted portions having short intersecting side walls cooperating to provide an enlarged target, and turning tool binding surfaces disposed around the bottom of said socket having elongated vertically convex binding surfaces in the bottom of said socket disposed at increasingly sharp binding angles toward said socket WILLIAM a.

' bottom. 

